Study of Acoustic Grinding Method developed for Tokaido Shinkansen

The rail grinding has been performed as one of the noise reduction methods of high-speed railway line in Japan since the inauguration of Tokaido Shinkansen. The noise reduction effect of the rail grinding, however, is not quantitatively grasped in the recent work by using the special train-set of rail grinding machines. In this study, we conducted the field measurement of wayside noise of high-speed train and rail surface roughness, before and after the rail grinding work in order to examine the grinding effect. It was found out from the field measurement result that the "trace pattern" of rail surface generated by grinding work has a big impact on the wayside noise of certain frequencies and it continues for several months. From this notice, we developed the new grinding strategy called "Acoustic Grinding" with the combination of grinding pressure and train-set speed by which we can decrease the grinding trace of rail surface. As a result, the most effective method was established for the rail grinding work to decrease the trace pattern and consequently, wayside noise.